Lewis played college football for the Miami Hurricanes before being selected by the St. Louis Rams in the first round of the 2001 NFL draft.

After redshirting as a true freshman, Lewis started in his second year and produced a career-high 72 tackles, four sacks, and one forced fumble.

As a rookie in 2001, Lewis played in nine games with three starts prior to being placed on injured reserve with a broken right foot, keeping him out of the Rams' Super Bowl XXXVI loss to the New England Patriots.

He registered 34 tackles, half a sack, 13 quarterback pressures, one forced fumble and one pass defensed.

A sprained ankle against the Pittsburgh Steelers hampered his playing time in the second half of the season.

He amassed career highs of 61 tackles and five sacks in addition to recording eight quarterback pressures, one forced fumble and two passes defensed.

He also helped unit rank 11th in the league in rushing yards per game, third in third-down efficiency and seventh in sacks per pass play.

For the season Lewis recorded 32 tackles, 3.5 sacks, a pass deflected and a fumble recovery.

Lewis signed with the New England Patriots on April 2, 2010, and was released during final cuts on September 3, 2010.